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Dynamical models for sand ripples beneath surface waves

Ken Haste Andersen·Marie-Line Chabanol·Martin van Hecke
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Abstract

We introduce order parameter models for describing the dynamics of sand ripple patterns under oscillatory flow. A crucial ingredient of these models is the mass transport between adjacent ripples, which we obtain from detailed numerical simulations for a range of ripple sizes. Using this mass transport function, our models predict the existence of a stable band of wavenumbers limited by secondary instabilities. Small ripples coarsen in our models and this process leads to a sharply selected final wavenumber, in agreement with experimental observations.

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Ken Haste Andersen, Marie-Line Chabanol, Martin van Hecke. 2001-02-26. Dynamical models for sand ripples beneath surface waves. https://doi.org/10.1103/physreve.63.066308

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